has anyone here used indium to solder to a non metal

[coppercone2]

I read alot of tall tales about being able to wet indium to many surfaces.

I cut a small strip of indium metal, and I also mixed up some indium/tin (50/50) in a smelt and planished it into some strips

I had four samples, 2 alumina and 2 microscope slides made out of glass. I washed them, soaked 1/2 in HCl and the other half in sodium hydroxide. I also soaked the solder in hydrochloric acid. Everything was washed in acetone too after being rinsed in distilled water, and it appeared to pass the "no bead" test.

I then heated them up and tried two different methods of application, one was to try to "feed" solder into it like soldering from a thin strip (1mm) and the other way was a preform, that is to put a flattened piece ontop of the substrate and then heat it


Anyway, in all cases, absolutely nothing happened. Its identical to feeding normal lead solder. With the preform I thought it was working, but actually as soon as I touched it to try to see what happens if I scrape it, it balled up into a lump and there was zero wetting.


I regard this as a total fail, it may be possible with ultrasonic but I have trouble believing the claims that its possible to use pure indium to solder glass with. I am not even seeing a HINT of any sort of adhesion.


I see you can buy a 'nickel felt' to help apply it. I have a feeling its a waste of money to try.

[coppercone2]

I got some sort of ultrasonic wand, I wanna see what happens if you poke it, and possibly make a butane heated tip for it to make a poor mans iron


The idea is to use a blower to keep the shaft / module cool and a ceramic coupler between the soldering iron tip and the shaft, to limit heat going into the crystals

[coppercone2]

it looks like you can drill into rubber with the ultrasonic wand. They use a special transformer instead of a piezo material.

what a bizzare contraption 


it looks like I can wet a microscope slide with indium that hangs on OK, but it keeps breaking. I need to try with a hot plate and lower ultrasonic settings. You can drag the wand through the molten indium and under neath it looks like a mirror

[coppercone2]

it looks like it works with indium, I made a T-joint between two ceramic heat spreader tiles.

that is so weird, there is actually a fillet.


wtf 

[coppercone2]